openssl/crypto/ec/curve448/arch_32/f_impl.c
Matt Caswell f53c77648c Update Curve448 copyright for 2018
Reviewed-by: Bernd Edlinger <bernd.edlinger@hotmail.de>
(Merged from https://github.com/openssl/openssl/pull/5105)
2018-02-20 12:59:30 +00:00

102 lines
3.1 KiB
C

/*
* Copyright 2017-2018 The OpenSSL Project Authors. All Rights Reserved.
* Copyright 2014 Cryptography Research, Inc.
*
* Licensed under the OpenSSL license (the "License"). You may not use
* this file except in compliance with the License. You can obtain a copy
* in the file LICENSE in the source distribution or at
* https://www.openssl.org/source/license.html
*
* Originally written by Mike Hamburg
*/
#include "field.h"
#if (defined(__OPTIMIZE__) && !defined(__OPTIMIZE_SIZE__) && !I_HATE_UNROLLED_LOOPS) \
|| defined(C448_FORCE_UNROLL)
# define REPEAT8(_x) _x _x _x _x _x _x _x _x
# define FOR_LIMB(_i,_start,_end,_x) do { _i=_start; REPEAT8( if (_i<_end) { _x; } _i++;) } while (0)
#else
# define FOR_LIMB(_i,_start,_end,_x) do { for (_i=_start; _i<_end; _i++) _x; } while (0)
#endif
void gf_mul(gf_s * RESTRICT cs, const gf as, const gf bs)
{
const uint32_t *a = as->limb, *b = bs->limb;
uint32_t *c = cs->limb;
uint64_t accum0 = 0, accum1 = 0, accum2 = 0;
uint32_t mask = (1 << 28) - 1;
uint32_t aa[8], bb[8];
int i, j;
for (i = 0; i < 8; i++) {
aa[i] = a[i] + a[i + 8];
bb[i] = b[i] + b[i + 8];
}
FOR_LIMB(j, 0, 8, {
accum2 = 0;
FOR_LIMB(i, 0, j + 1, {
accum2 += widemul(a[j - i], b[i]);
accum1 += widemul(aa[j - i], bb[i]);
accum0 += widemul(a[8 + j - i], b[8 + i]);
}
); accum1 -= accum2; accum0 += accum2;
accum2 = 0;
FOR_LIMB(i, j + 1, 8, {
accum0 -=
widemul(a[8 + j - i], b[i]);
accum2 +=
widemul(aa[8 + j - i],
bb[i]);
accum1 += widemul(a[16 + j - i], b[8 + i]);
}
);
accum1 += accum2;
accum0 += accum2;
c[j] = ((uint32_t)(accum0)) & mask;
c[j + 8] = ((uint32_t)(accum1)) & mask;
accum0 >>= 28; accum1 >>= 28;
});
accum0 += accum1;
accum0 += c[8];
accum1 += c[0];
c[8] = ((uint32_t)(accum0)) & mask;
c[0] = ((uint32_t)(accum1)) & mask;
accum0 >>= 28;
accum1 >>= 28;
c[9] += ((uint32_t)(accum0));
c[1] += ((uint32_t)(accum1));
}
void gf_mulw_unsigned(gf_s * RESTRICT cs, const gf as, uint32_t b)
{
const uint32_t *a = as->limb;
uint32_t *c = cs->limb;
uint64_t accum0 = 0, accum8 = 0;
uint32_t mask = (1 << 28) - 1;
int i;
assert(b < 1 << 28);
FOR_LIMB(i, 0, 8, {
accum0 += widemul(b, a[i]); accum8 += widemul(b, a[i + 8]);
c[i] = accum0 & mask; accum0 >>= 28;
c[i + 8] = accum8 & mask; accum8 >>= 28;
});
accum0 += accum8 + c[8];
c[8] = ((uint32_t)accum0) & mask;
c[9] += (uint32_t)(accum0 >> 28);
accum8 += c[0];
c[0] = ((uint32_t)accum8) & mask;
c[1] += (uint32_t)(accum8 >> 28);
}
void gf_sqr(gf_s * RESTRICT cs, const gf as)
{
gf_mul(cs, as, as); /* Performs better with a dedicated square */
}